Meta tags that Google understands

Meta tags are a great way for webmasters to provide search engines with information about their sites. Meta tags can be used to provide information to all sorts of clients, and each system processes only the meta tags they understand and ignores the rest. Meta tags are added to the <head> section of your HTML page and generally look like this:

This tag provides a short description of the page. In some situations this description is used as a part of the snippet shown in the search results. More information

<title>The Title of the Page</title>

While technically not a meta tag, this tag is often used together with the "description". The contents of this tag are generally shown as the title in search results (and of course in the user's browser). More information

These meta tags can control the behavior of search engine crawling and indexing. The robots meta tag applies to all search engines, while the "googlebot" meta tag is specific to Google. The default values are "index, follow" (the same as "all") and do not need to be specified. We understand the following values (when specifying multiple values, separate them with a comma):

unavailable_after:[date]: lets you specify the exact time and date you want to stop crawling and indexing of this page

noimageindex: lets you specify that you do not want your page to appear as the referring page for an image that appears in Google search results.

none: is equivalent to noindex, nofollow.

You can now also specify this information in the header of your pages using the "X-Robots-Tag" HTTP header directive. This is particularly useful if you wish to limit indexing of non-HTML files like graphics or other kinds of documents. More information about robots meta tags

<meta name="google" content="nositelinkssearchbox" />

When users search for your site, Google Search results sometimes display a search box specific to your site, along with other direct links to your site. This meta tag tells Google not to show the sitelinks search box. Learn more about sitelinks search box.

<meta name="google" content="notranslate" />

When we recognize that the contents of a page are not in the language that the user is likely to want to read, we often provide a link to a translation in the search results. In general, this gives you the chance to provide your unique and compelling content to a much larger group of users. However, there may be situations where this is not desired. This meta tag tells Google that you don't want us to provide a translation for this page.

<meta name="google-site-verification" content="..." />

You can use this tag on the top-level page of your site to verify ownership for Webmaster Tools. Please note that while the values of the "name" and "content" attributes must match exactly what is provided to you (including upper and lower case), it doesn't matter if you change the tag from XHTML to HTML or if the format of the tag matches the format of your page. More information

This defines the page's content type and character set. Make sure that you surround the value of the content attribute with quotes - otherwise the charset attribute may be interpreted incorrectly. We recommend using Unicode/UTF-8 where possible. More information

<meta http-equiv="refresh" content="...;url=..." />

This meta tag sends the user to a new URL after a certain amount of time, and is sometimes used as a simple form of redirection. However, it is not supported by all browsers and can be confusing to the user. The W3C recommends that this tag not be used. We recommend using a server-side 301 redirect instead.

Other points to note:

Google can read both HTML and XHTML-style meta tags, regardless of the code used on the page.

With the exception of verify, case is generally not important in meta tags.

This is not an exclusive list of available meta tags, and you should feel free to use unlisted meta tags if they are important to your site. Just remember that Google will ignore meta tags it doesn't know.